Met Éireann said today will be blustery with showers or longer spells of rain at times, most frequent over the northern half of the country.
However, there will be a few sunny spells also. Highest temperatures today will range from 7C to 10C.
It will be largely cloudy tonight with some patchy light rain or drizzle.
Lowest temperatures will fall back to between 4C and 9C and it will be coldest in the southeast.
The forecaster said there will be a good deal of cloud tomorrow with just occasional bright or sunny spells developing.
It will be dry apart from a little patchy light rain or drizzle, becoming persistent in the northwest later. Highest temperatures of 8C to 11C are expected.
There will be occasional outbreaks of rain and drizzle, mainly in the north and west, on Thursday night. It will be a frost-free night with lowest temperatures of 7C to 9C.
Met Éireann said Friday will be rather cloudy again with patches of light rain and drizzle, mainly in the west. Sunny spells will break through occasionally further east. Highest temperatures will range from 10C to 12C.
After a dry start, a spell of rain is expected on Saturday, and it will move south-eastwards across the country. The forecaster said daytime temperatures will reach 9C or 10C over Ulster and Connacht and 11C or 12C across Munster and Leinster.
Temperatures are expected to drop below zero on Saturday night with a widespread frost setting in. Some mist and fog patches will develop too as the winds ease light and variable.
“Current indications suggest that Sunday and Monday will be mainly dry days with some sunny spells, and although Sunday is expected to be a cold day, with frost after dark, it will turn slightly milder again on Monday,” Met Éireann said.